Crown rise due to competition drives biomass allocation in silver birch
Bibliographic record
Abstract
This study tests the hypothesis that the aboveground structure of silver birch (Betula pendula L.) is derivable from crown rise across a range of social positions of trees. Data were measured in 30-year-old birch monocultures of three different initial spacings. As suggested by the pipe model, there was a strong linear correlation between the total cross-sectional area of branches and that of stem at crown base. Foliage mass correlated with stem basal area at crown base. An allometric relationship was found between foliage mass and crown length, and the mean length (weighted by basal area) of branches correlated linearly with crown length. Pipe ratios of branches and foliage were found to be independent of slenderness (= tree height / breast height diameter). The proportion of stem in aboveground biomass increased from 80% to 96% when the slenderness index increased, the proportions of branches and leaves decreasing, respectively. For crown biomass, the proportion of foliage was greater in the more slender stems, accompanied with a corresponding decrease in the proportion of stems, while the share of branches remained rather constant. The ratio of productive (foliage) and nonproductive (stem plus branches) biomass inside the crown was positively correlated with slenderness, but in the whole tree, the ratio declined with increasing slenderness. The results of this study support the theory of functional balance and seem to be in conflict with the priority principle of allocation.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".